This memorandum provides a technical review of the report, Geochemical Pit Lake Predictive Model, Rosemont Copper Project (Tetra Tech, 2010). This review was undertaken, and the Technical Memorandum prepared, at the request of SWCA and the Coronado National Forest, in accordance with a Statement of Work and Request for Cost Estimate d from Mr. Dale Ortman da ted February 17, 2010. This memorandum was prepared by Vladimir Ugorets a nd Stephen Day of SRK Consulting, Inc. (SRK).